From: Sam R. <samruohola@yahoo.com>
To: Sam R. <samruohola@yahoo.com>
To: pgsql-performance@lists.postgresql.org <pgsql-performance@lists.postgresql.org>
Subject: Re: To keep indexes in memory, is large enough effective_cache_size enough?
Date: Wed, 19 Sep 2018 09:15:03 +0000 (UTC)
Message-ID: <954477769.6489282.1537348503194@mail.yahoo.com> (raw)
In-Reply-To: <1321418371.5650982.1537346138600@mail.yahoo.com>
References: <1321418371.5650982.1537346138600.ref@mail.yahoo.com>
<1321418371.5650982.1537346138600@mail.yahoo.com>
Hi!
Is is possible to force PostgreSQL to keep an index in memory? The data in db table columns is not needed to be kept in memory, only the index. (hash index.)
It would sound optimal in our scenario.I think Oracle has capability to keep index in memory (in-memory db functionality). But does PostgreSQL have such a functionality? (I keep searching.)
I have read:
Tuning Your PostgreSQL Server - PostgreSQL wiki
(effective_cache_size, shared_buffers)
I have seen responses to:
PostgreSQL Index Caching
Should I actually set shared_buffers to tens of gigabytes also, if I want to keep one very big index in memory?
I ma also reading a PG book.
Best Regards, Sam
On Wednesday, September 19, 2018 11:40 AM, Sam R. <samruohola@yahoo.com> wrote:
Hi!
Related to my other email (size of index in memory),
Other questions,
Q: To keep _index(es)_ in memory, is large enough effective_cache_size enough?
Q: Size of shared_buffers does not matter regarding keeping index in memory?
Or have I missed something, does it matter (to keep indexes in memory)?
Background info: I have plans to use hash indexes: very large amount of data in db tables, but (e.g. hash) indexes could be kept in memory.
I am using PostgreSQL 10. I could start to use PostgreSQL 11, after it has been released.
Best Regards, Sam
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Subject: Re: To keep indexes in memory, is large enough effective_cache_size enough?
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